I do think it was a legitimate question to ask Ms. Bachmann, as she has stated that she is submissive to her husband and she is promoting "family values." I don't think Chris Wallace was being sexist, and I'm glad that Fox News actually put that issue upfront, rather than hiding it.
Do I think every female candidate should be asked that? No! Not even those who profess themselves to be Christian. I think this was legitimate for Ms. Bachmann because she had publicly stated it and it was something that had been brought up recently about her.

It is true that over all female candidates get treated more harshly than male candidates. We still live in a sexist society. Its in both parties, unfortunately. Even though the Democratic party claims to fight for women's equality, it runs rampant in that party too. Granted, the Democratic party has fought for some women's issues...but really not hard enough in my opinion.
Many people that I know naively think that women and men are treated equally in our society (with only rare exceptions...like the mean mainstream (liberal) media). My husband thinks it is a dead issue. He doesn't argue this one with me, as I state adamantly that it is still a problem...but he believes it isn't an issue, nevertheless.
I think many people think we're "Post-Feminism" and that we need to stop whining so much.
I am all for speaking out against mistreatment of female candidates, from either party. I think Palin was mistreated, compared to her male cohorts. I think many complaints against Palin were legitimate...don't get me wrong...but at the beginning especially, people were bashing her about her Down's Syndrome kid, about her being a working mom (governor and a mom of a Down's Syndrome kid...oh the horror!!!), making fun of her voice, making fun of her looks (or focusing too much on it).
We aren't that evolved of a society...sorry to tell ya.